SEAT AND UPHOLSTERY FASTENING LINK

Abstract

It is an object, a seat and a seat fastening element, which achieve a stable fixing of a cover solely by means of the fastening element. A cover fastening element (9) comprises a cover fixing part (12) and an engaging part (13).When the engaging part (13) engages with a section in engagement by sandwiching the section in engagement between an outer engaging section (17) and an inner engaging section (18), a tensile force of the reference is generated, and an inner projection (20) of the inner engaging section (18) is pressed against an inner surface of the section in engagement to be a pivot point, and a projection (19) at a distal end of the outer engaging section (17) is pressed against an outer surface of the section in engagement to receive a reaction force from the outer surface and to be a point of action in response to the tensile force.The projection (19) thus receives the reaction force, which maintains a balance between the rotational moment based on the tensile force of the reference and the rotational moment based on the acting force acting on the reference fixing part (12).

Description

Seat and cover fixing member

[0001] The present invention relates to a sheet in which a skin covers the front surface of a substrate, and a skin fixing member.

[0002] BACKGROUND ART Conventionally, seats attached to vehicles such as automobiles have been known to have a structure in which a cover covers the front surface of a base body, and edges of the cover are fastened to the base body by fastening members.

[0003] For example, in a portion above an armrest storage compartment in the middle of a three-row rear seat (see, for example, FIG. 1 ), a fixing structure using a clip 43, such as the one shown in FIG. 14 , is known for fastening an edge of an upholstery to a resin base using a terminal fastening member such as a clip. In this fixing structure, the edge of the upholstery 42 covering the front side X1 of the base 41 is fastened (i.e., pinpoint fastened) to the lower part of the base 41 above the armrest storage compartment 40 Z1, which stores the armrest AR, using the clip 43. As a result, the clip 43 is easily dislodged due to the tensile force of the upholstery 42, making it difficult to maintain a constant tension on the upholstery 42. Furthermore, the provision of a hole for clip fastening in the upholstery 42 creates a parting line. Therefore, this upholstery fixing structure results in poor appearance and a high probability of the fastening member becoming dislodged.

[0004] Another known fixing structure uses a cover finisher with a J-shaped cross section that can be surface-fixed as a locking member with a larger locking area than a clip. In this fixing structure, the cover finisher is fixed to the edge of the cover and locked into a slit formed in the base. However, this fixing structure requires a slit to lock the cover finisher to the base, which requires a separate member to hide the slit. Therefore, this cover fixing structure also results in poor appearance, increased manufacturing costs, and reduced convenience.

[0005] In order to solve the above problems (poor appearance and maintenance of the engaged state), there is a demand for a skin fixing structure that can maintain the engaged state of the skin edge without adding additional parts or causing poor appearance.

[0006] To meet such demands, for example, a cover fixing structure shown in Fig. 15 is known from Patent Document 1. In the seat shown in Fig. 15, a seat cushion 90 is attached to a frame 71, and a cover 80 covers the surface of the seat cushion 90. An end of the cover 80 is fixed to a lower edge 71a of the frame 71 by a fixing member 50, and the space below the seat cushion 90 is covered by a cover member 60, so that the fixing point of the cover end cannot be seen from the outside.

[0007] Specifically, the fixing member 50 shown in FIG. 15 is a Y-shaped member in cross section and includes an inner edge 51 disposed inside the frame 71, an outer edge 54 disposed outside the frame 71, and a lower protrusion 52 protruding downward. An end of the skin 80 is sewn to a thin-walled portion 55 of the inner edge 51 at a stitched portion 55a. A locking piece 53 provided on the inner edge 51 locks onto the lower edge 71a of the frame 71, and the lower edge 71a is sandwiched between the inner edge 51 and the outer edge 54, thereby locking the fixing member 50 to the lower edge 71a of the frame 71. The lower protrusion 52 engages with the upper end 61 of the cover member 60. Therefore, the fixing member 50 maintains the fixed state of the end of the skin 80 by engaging with the lower edge 71a of the frame 71 and the upper end 61 of the cover member 60.

[0008] 15, when a strong tensile force A acts on the skin 80, the fixing member 50 may rotate in the direction of arrow B, disengaging the locking piece 53 of the fixing member 50 from the lower edge 71a of the frame 71 and disengaging the lower protrusion 52 from the upper end 61 of the cover member 60. Therefore, even with the structure shown in FIG. 15, there is room for improvement in terms of maintaining the locked state of the edge of the skin.

[0009] Patent No. 5196227

[0010] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a seat and a skin fixing member that can stably fix the edge of the skin using only a fixing member without adding any additional parts.

[0011] In order to solve the above-mentioned problems, the seat of the present invention is a seat comprising a base, a skin covering the front surface of the base, and a skin fixing member that fixes an end of the skin to the base at an edge of the rear surface of the base, wherein the base has an engaged portion that protrudes rearward from the edge of the rear surface of the base, the engaged portion having an outer surface facing outward and an inner surface facing inward of the base, the end of the skin extends to the rear surface side of the base beyond the engaged portion, the skin fixing member comprises a skin attachment portion to which the end of the skin is attached, and a locking portion that is arranged closer to the engaged portion than the skin attachment portion and is locked to the locked portion, the end of the skin is locked to the locked portion via the skin attachment portion, the locking portion has an outer locking piece that abuts on the outer surface of the engaged portion and an inner locking piece that abuts on the inner surface of the engaged portion, and the inner locking piece the outer locking piece has an inner protruding portion that protrudes toward the inner surface of the locked portion, and the outer locking piece has a reaction force receiving portion at its tip that receives a reaction force from the outer surface of the locked portion, the locking portion is locked to the locked portion with the outer locking piece sandwiched between the outer locking piece and the inner locking piece, and the reaction force receiving portion is configured to receive a reaction force from the outer surface of the locked portion with the inner protruding portion as a fulcrum due to the tension of the skin, and the reaction force receiving portion is configured to receive the reaction force such that the rotational moment caused by the tension of the skin received by the skin attachment portion with the inner protruding portion as the center of rotation is balanced with the rotational moment caused by the acting force acting on the skin attachment portion by applying an acting force to the skin attachment portion in a direction perpendicular to the direction of the tension and in a direction approaching the locked portion due to the reaction force.

[0012] 1 is a perspective view showing the overall configuration of a third-row rear seat as an example of a seat according to an embodiment of the present invention, illustrating a state before the armrest is stored in the armrest storage section.

[0023] FIG. 1 is a perspective view showing a state after the armrest of the third-row rear seat of FIG. 1 has been stored in the armrest storage section.

[0024] FIG. 1 is an enlarged perspective view showing a seam between the upholstery and a lower component of the base body at the upper end of the armrest storage section of FIG. 1.

[0025] FIG. 1 is an explanatory cross-sectional view showing the arrangement of the upper component of the base body, the upholstery, and the upholstery fixing member at the upper end of the armrest storage section of FIG. 1.

[0026] FIG. 4 is an enlarged cross-sectional view of the upper component of the base body, the upholstery, and the upholstery fixing member of FIG. 4, showing a V-V cross section of the upholstery fixing member of FIG. 6.

[0027] FIG. 5 is a perspective view of the upholstery fixing member of FIG. 5.

[0028] FIG. 6 is a cross-sectional view showing a VII-VII cross section of the upholstery fixing member of FIG. 6, illustrating the positional relationship between the upholstery fixing member, the upper component of the base body, and the upholstery at the position where a slit is formed in the upholstery fixing member.

[0029] FIG. 5 is an explanatory cross-sectional view showing a state in which an inner protrusion, which serves as a fulcrum when the upholstery attachment portion of the upholstery fixing member of FIG. 5 is subjected to tension of the upholstery, is pressed against the inner surface of the locked portion. 10 is a cross-sectional explanatory diagram showing a state in which the protrusion serving as a reaction force receiving portion at the tip of the outer locking piece in FIG. 8 receives a reaction force from the outer surface of the locked portion and becomes a point of force. FIG. 11 is a cross-sectional explanatory diagram showing a state in which the upholstery attachment portion in FIG. 9 receives an acting force in a direction perpendicular to the tension of the upholstery and in a direction approaching the locked portion and becomes a point of action. FIG. 12 is a cross-sectional explanatory diagram showing the inner protrusion, protrusion, and upholstery attachment portion in FIGS. 8 to 10 function as a fulcrum, a point of force, and a point of action. FIG. 13 is a cross-sectional explanatory diagram showing the operation of inserting a finger between the upholstery and the armrest at the upper end of the armrest storage portion in FIG. 4 to remove the armrest. FIG. 14 is a cross-sectional explanatory diagram of a modified example of the seat of the present invention, in which the outer locking piece has an inclined tip as a reaction force receiving portion. FIG. 15 is a cross-sectional diagram showing a structure in which the upholstery of a conventional seat is fastened at points with clips. FIG. 16 is a cross-sectional diagram showing a structure in which the upholstery of a conventional seat is fastened to the lower edge of the frame with a fixing member having a Y-shaped cross section.

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A seat and a seat fixing member according to an embodiment of the present invention will be described in detail below with reference to the drawings.

[0014] (Overall configuration of the seat) As one example of an embodiment of the seat of the present invention, a seat 1 shown in Figures 1 and 2 is a three-row rear seat of a vehicle. This seat 1 has main seats 2 on both sides and a center seat 3 in the middle. In the drawings used in this embodiment, the front-to-rear direction of the seat 1 is indicated by arrow X (front side X1, rear side (rear face) X2), the width direction is indicated by arrow Y, and the up-down direction is indicated by arrow Z (upper side Z1, lower side Z2).

[0015] As shown in Figures 1 to 4, the center seat 3 includes a base body 4 with an armrest storage section 7, a headrest 5, an armrest 6, a skin 8 that covers the upper part of the base body 4 (specifically, the upper component part 4b), and a skin fixing member 9 (hereinafter referred to as fixing member 9) for fixing the skin 8 to the base body 4.

[0016] As shown in Figures 3 and 4, the armrest storage section 7 is disposed adjacent to the outer side (lower side Z2 in Figures 3 and 4) of the end 8a of the skin 8 (hereinafter referred to as the skin end 8a) that extends to the rear side X2 of the base body 4. The armrest 6 shown in Figures 1 and 2 is stored in an upright position in the armrest storage section 7, and is able to support the back of a seated occupant. On the other hand, when the armrest 6 is removed from the armrest storage section 7 and folded forward toward the front side X1, it can be used as an armrest for the occupants of the main seats 2 on both sides.

[0017] As shown in Figures 4 and 5, the base body 4 has a lower component 4a and an upper component 4b located above the lower component 4a in a dimension Z1. The lower component 4a and the upper component 4b are integrally molded from resin to form the vertical rectangular parallelepiped base body 4, which serves as the main body of the seat back capable of supporting the back of a seated occupant. As shown in Figure 4, the base body 4 is supported by a frame 10, and the rear side X2 of the base body 4 is covered with a backboard 11 and a skin 8.

[0018] The lower component 4a is a vertical, generally plate-shaped portion that forms the bottom wall (the wall on the rear side X2) of the armrest storage portion 7. As shown in Fig. 5, the lower component 4a of this embodiment has a receiving portion 4a1 that receives the tip of a cover attachment portion 12 of the fixing member 9 (described later) and an engaging portion 4a2 with which the tip engages.

[0019] As shown in Figure 4, the upper component 4b protrudes above the lower component 4a Z1 and toward the front X1 more than the lower component 4a, forming a step between it and the lower component 4a in the front-to-rear direction X. Utilizing this step, the armrest storage section 7, in which the rectangular parallelepiped block-shaped armrest 6 can be stored, is formed below the upper component 4b Z2 and in front of the lower component 4a X1.

[0020] A front surface 4b2 of the upper constituent part 4b is provided with ridges (pleats) 4d extending in the up-down direction Z. A plurality of the ridges 4d are arranged side by side in the width direction Y of the sheet 1.

[0021] As shown in Figures 4 and 5, a locking portion 4b1 is provided on the rear surface 4b3 of the upper component 4b. The locking portion 4b1 protrudes from an edge 4b31 on the lower side Z2 of the rear surface 4b3 of the upper component 4b toward the rear side X2. The locking portion 4b1 has an outer surface 4b11 facing the outside of the upper component 4b (the lower side Z2 in Figure 5) and an inner surface 4b12 facing the inside (the upper side Z1 in Figure 5). Furthermore, an inclined surface 4b13 is formed at the tip end (end on the rear side X2) of the inner surface 4b12, which tapers toward the tip end (rear side X2) of the locking portion 4b1. A gap 4c is formed between the locking portion 4b1 and the lower component 4a. A fixing member 9 is fitted into the gap 4c.

[0022] As shown in FIG. 4, the skin 8 covers the front surface 4b2 of the upper component 4b of the base 4 and also covers the rear surface side X2 of the backboard 11.

[0023] As shown in FIG. 5, the skin end 8a extends from the lower end (end on the lower side Z2) of the front surface 4b2 of the upper component 4b toward the rear surface side X2, beyond the locked portion 4b1, and onto the rear surface side X2 of the base body.

[0024] (Configuration of fixing member 9) The fixing member 9 is configured to fix the skin end portion 8a to the locked portion 4b1 of the upper component 4b at the edge 4b31 of the rear surface 4b3 of the upper component 4b of the base 4 shown in Figures 4 and 5. Specifically, as shown in Figures 5 and 6, the fixing member 9 includes a skin attachment portion 12 to which the skin end portion 8a is attached, a locking portion 13 that locks to the locked portion 4b1, and a connecting arm portion 14 that connects the skin attachment portion 12 and the locking portion 13. The locking portion 13 is located closer to the locked portion 4b1 than the skin attachment portion 12 (front side X1 in Figure 5).

[0025] As shown in Fig. 6, the fixing member 9 of this embodiment is configured as a long strip-shaped member extending in a first direction D1 in which the upholstery attachment portions 12 and the locking portions 13 are aligned and in a second direction D2 perpendicular to the first direction D1. Note that the first direction D1 corresponds to the front-to-rear direction X of the seat 1 in the attached state of the fixing member 9 shown in Fig. 5. The second direction D2 corresponds to the width direction Y of the seat 1 shown in Fig. 3 in the attached state of the fixing member 9 shown in Fig. 5.

[0026] A slit 22 (see FIGS. 6 and 7) is formed near the center in the second direction D2 of the belt-shaped member that constitutes the fixing member 9, by removing the locking portion 13 and the connecting arm portion 14. The locking portion 13 and the connecting arm portion 14 are absent in the area where the slit 22 is formed, making it easier for the skin end portion 8a to bend upward Z1 when a user places their fingers FR (see FIG. 12) in the armrest storage portion 7.

[0027] The skin attachment portion 12 has a shape to which the skin end portion 8a can be attached. Specifically, as shown in FIG. 5 , it is a portion that extends linearly in the front-to-rear direction X and has a flat portion 15 that linearly guides the skin end portion 8a toward the rear side X2. The skin end portion 8a is secured by sewing as shown in the stitching portion 16 while being wrapped around the skin attachment portion 12. The skin attachment portion 12 only needs to have a thickness that allows the skin end portion 8a to be sewn to the skin attachment portion 12. Note that the skin end portion 8a may be secured to the skin attachment portion 12 by a method other than sewing, such as adhesive or metal fittings.

[0028] The skin end portion 8a is attached to the locked portion 4b1 via the skin attachment portion 12 in a state where it is pulled toward the rear side X2 while moving away from the outer surface 4b11 of the locked portion 4b1 toward the outside of the upper component 4b of the base 4 (the lower side Z2 in Figures 4 and 5). The tip portion of the skin attachment portion 12 (the end portion on the rear side X2) is supported by the receiving portion 4a1 of the lower component 4a of the base 4, and is prevented from slipping out of the receiving portion 4a1 by the engagement portion 4a2 engaging with the tip portion.

[0029] The connecting arm 14 has a stepped portion 21 that bends in a direction away from the skin edge 8a, making it easier for the skin edge 8a to bend upward Z1 when the user places their fingers FR (see FIG. 12) in the armrest storage portion 7.

[0030] 5, the locking portion 13 has an outer locking piece 17 and an inner locking piece 18 that are spaced apart from each other, i.e., the outer locking piece 17 abuts against the outer surface 4b11 of the locked portion 4b1, and the inner locking piece 18 abuts against the inner surface 4b12 of the locked portion 4b1. The locking portion 13 is locked to the locked portion 4b1 with the outer locking piece 17 and the inner locking piece 18 sandwiching the locked portion 4b1.

[0031] The inner locking piece 18 has an inner protrusion 20 that protrudes toward the inner surface 4b12 of the locked portion 4b1. In this embodiment, the inner protrusion 20 protrudes inward into the gap between the outer locking piece 17 and the inner locking piece 18, and is disposed at the base of the inner locking piece 18. The inner protrusion 20 makes pinpoint contact with the inclined surface 4b13 on the tip side (rear surface side X2) of the inner surface 4b12 of the locked portion 4b1 at a contact point CP.

[0032] Furthermore, the inner locking piece 18 has an inclined surface 18a that is inclined in a direction away from the inner surface 4b12 of the locked portion 4b1 as it approaches the tip of the inner locking piece 18.

[0033] The outer locking piece 17 has a protrusion 19 at its tip end 17a as a reaction force receiving portion that receives a reaction force F2 from the outer surface 4b11 of the locked portion 4b1.

[0034] In this embodiment, the reaction force receiving portion includes a protrusion 19 that protrudes from the tip 17a of the outer locking piece 17 toward the outer surface 4b11 of the locked portion 4b1. This protrusion 19 protrudes inward into the gap between the outer locking piece 17 and the inner locking piece 18. The protrusion 19 is strongly pressed against and bites into the outer surface 4b11 of the locked portion 4b1 by a rotation moment M1 (see FIG. 11 ) of the fixing member 9 around the contact point CP of the inner protrusion 20 that is generated by the tension of the skin end portion 8a toward the front side X1.

[0035] In this embodiment, the tip 17a of the outer locking piece 17 is inclined toward the outer surface 4b11 of the locked portion 4b1 with respect to the extension direction of the skin attachment portion 12 (the vertical direction X in FIG. 5 ). This inclined tip 17a itself can also function as a reaction force receiving portion (i.e., be included in the reaction force receiving portion).

[0036] In the fixing member 9 of this embodiment, the locking portion 13 is locked to the locked portion 4b1 with the locked portion 4b1 sandwiched between the outer locking piece 17 and the inner locking piece 18. In this state, the inner protrusion 20 of the inner locking piece 18 is in pinpoint contact with the inclined surface 4b13 on the tip side of the inner surface 4b12 of the locked portion 4b1 at the position of contact point CP. Furthermore, the protrusion 19 provided on the tip end 17a of the outer locking piece 17 is strongly pressed against the outer surface 4b11 of the locked portion 4b1, biting into it.

[0037] Furthermore, as shown in FIG. 5, when viewed in a direction (vertical direction Z in FIG. 5) perpendicular to the direction in which the skin attachment portion 12 and the locking portion 13 are aligned (front-to-back direction X in FIG. 5), the flat portion 15 of the skin attachment portion 12 is located farther from the inner protrusion 20 of the inner locking piece 18 than the convex portion 19 and tip end 17a of the outer locking piece 17, which function as the reaction force receiving portion described above.

[0038] The engaging portion 13 is engaged with the engaged portion 4b1 while the outer engaging piece 17 and the inner engaging piece 18 sandwich the engaged portion 4b1, and is configured so that due to the tension T (see Figure 8) of the skin end portion 8a, the convex portion 19 (reaction force receiving portion) at the tip side of the outer engaging piece 17 receives a reaction force F2 (see Figure 9) from the outer surface 4b11 of the engaged portion 4b1, with the contact point CP of the inner protrusion 20 of the inner engaging piece 18 as the fulcrum.

[0039] 11, the protrusion 19 serving as the reaction force receiving portion applies an acting force F3 to the skin attachment portion 12 in a direction perpendicular to the direction of the tension T of the skin end portion 8a (the vertical direction Z in FIG. 10) and in a direction approaching the locked portion 4b1 (upward direction Z1) due to the reaction force F2 received from the outer surface 4b11 of the locked portion 4b1, and is configured to receive a reaction force that can balance out the rotational moment M1 due to the tension T of the skin 8 received by the skin attachment portion 12, with the rotational center being the contact point CP of the inner protrusion 20, and the rotational moment M2 due to the acting force F3 acting on the skin attachment portion 12. Specific effects will be described in detail below.

[0040] 1 and 2, the seat 1 of this embodiment includes a fixing member 9 in which a locking portion 4b1 protrudes from an edge 4b31 of a rear surface 4b3 of an upper component 4b of a base 4 toward the rear side X2, and which is locked to the locking portion 4b1 to fix an upholstery end portion 8a to the locking portion 4b1 of the upper component 4b, as shown in FIGS. 4 and 5. This fixing member 9 is configured such that the locking portion 13, which is locked to the locking portion 4b1, is unlikely to come off even when the upholstery attachment portion 12 receives tension T on the upholstery 8 in a direction toward the front surface 4b2 of the upper component 4b. Specifically, locking portion 13 has outer locking piece 17 that abuts against outer surface 4b11 of locked portion 4b1 and inner locking piece 18 that abuts against inner surface 4b12 of locked portion 4b1, and is locked to locked portion 4b1 with outer locking piece 17 and inner locking piece 18 sandwiching locked portion 4b1. Inner locking piece 18 has inner protrusion 20 that protrudes toward inner surface 4b12 of locked portion 4b1. Outer locking piece 17 has protrusion 19 at its tip end 17a as a reaction force receiving portion that receives reaction force F2 from the outer surface 4b11 of locked portion 4b1.

[0041] 8 , in the fixing member 9 of this embodiment, when the skin end portion 8a attached to the skin attachment portion 12 is pulled and the locking portion 13 is locked to the locked portion 4b1 with the outer locking piece 17 and the inner locking piece 18 sandwiching the locked portion 4b1, a tension T is generated in the skin end portion 8a in a direction (forward side X1) toward the front surface 4b2 of the upper component 4b of the base 4. This tension T presses (see pressing force F1) the inner protrusion 20 of the inner locking piece 18 against the inner surface 4b12 of the locked portion 4b1 (specifically, the inclined surface 4b13 on the tip side of the inner surface 4b12) at the position of contact point CP, which serves as a fulcrum.

[0042] 9, the protrusion 19 (reaction force receiving portion) at the tip end of the outer locking piece 17 is pressed against the outer surface 4b11 of the locked portion 4b1 and receives a reaction force F2 from the outer surface 4b11, becoming a point of force. The reaction force F2 causes the protrusion 19 to apply an acting force F3 to the skin attachment portion 12 in a direction perpendicular to the direction of the tension T (the vertical direction Z in FIG. 10) and in a direction approaching the locked portion 4b1 (upward direction Z1).

[0043] As a result, as shown in Figure 11, it is possible to balance the rotational moment M1 due to the tension T of the skin 8 that the skin attachment portion 12 receives, with the contact point CP of the inner protrusion 20 as the center of rotation, and the rotational moment M2 due to the acting force F3 that acts on the skin attachment portion 12.

[0044] Therefore, with this fixing member 9, the balance of the two rotational moments M1, M2 acting on the upholstery attachment portion 12 prevents the fixing member 9 from rotating. As a result, the locking portion 13 of the fixing member 9 can maintain a state in which it is locked to the locked portion 4b1 of the base body by sandwiching the locked portion 4b1 from the inside and outside with the outer locking piece 17 and the inner locking piece 18, and the locking portion 13 will not come off the locked portion 4b1. Therefore, no additional member for preventing the locked portion 4b1 from coming off is required in addition to the fixing member 9, and it is possible to stably fix the upholstery edge 8a using only the fixing member 9 without adding any additional parts to the seat 1.

[0045] (2) In the seat 1 of this embodiment, the reaction force receiving portion includes a protrusion 19 that protrudes from the tip 17a of the outer locking piece 17 toward the outer surface 4b11 of the locked portion 4b1. Therefore, the protrusion 19 bites into the outer surface 4b11 of the locked portion 4b1, thereby ensuring that the reaction force F2 is received from the outer surface 4b11.

[0046] (3) In the seat 1 of this embodiment, the reaction force receiving portion includes not only the above-described convex portion 19 but also the inclined tip portion 17a. With this configuration, the reaction force receiving portion further includes the tip portion 17a of the outer locking piece 17 that is inclined in a direction toward the outer surface 4b11 of the locked portion 4b1 with respect to the extension direction of the cover attachment portion 12. Therefore, this inclined tip portion 17a and the above-described convex portion 19 dig into the outer surface 4b11 of the locked portion 4b1, and it is possible to reliably receive the reaction force F2 from the outer surface 4b11.

[0047] As a modified example of the present invention, even if the outer locking piece 17 does not have the protrusion 19, as shown in Figure 13, if the reaction force receiving portion has a tip 17a of the outer locking piece 17 that is inclined in a direction toward the outer surface 4b11 of the locked portion 4b1 with respect to the extension direction of the skin attachment portion 12, this inclined tip 17a will bite into the outer surface 4b11 of the locked portion 4b1, and it will be possible to reliably receive the reaction force F2 from the outer surface 4b11.

[0048] Here, in order to make the tip 17a of the outer locking piece 17 inclined in a direction toward the outer surface 4b11 of the locked portion 4b1 relative to the extension direction of the skin attachment portion 12, the outer locking piece 17 can be positioned so that it is along a line L2 that is inclined in a direction approaching the inner locking piece 18 relative to the extension line L1 of the flat portion 15 of the skin attachment portion 12.

[0049] (4) In the seat 1 of this embodiment, the cover attachment portion 12 has a flat surface 15 that linearly guides the cover edge portion 8a toward the rear side X2. With this configuration, the cover edge portion 8a follows the flat surface 15 (see FIG. 5 ) of the cover attachment portion 12, thereby maintaining a uniform appearance of the seat 1.

[0050] (5) In the seat 1 of this embodiment, the skin edge 8a is fixed in a state in which it is wrapped around the skin attachment portion 12. This configuration makes it possible to firmly fix the skin edge 8a to the skin attachment portion 12. At the same time, the seam P between the skin edge 8a and another member, in this embodiment, the lower component portion 4a of the base 4 shown in Figures 3 and 4, tends to be clearly and neatly formed.

[0051] (6) In the seat 1 of this embodiment, the thickness of the skin attachment portion 12 is such that the skin end portion 8a can be sewn to the skin attachment portion 12. This configuration makes it easier to sew the skin end portion 8a to the skin attachment portion 12. At the same time, the seam P (see FIGS. 3 and 4) between the skin end portion 8a and the other member (the lower component portion 4a) tends to appear clearer and neater.

[0052] (7) In the seat 1 of this embodiment, as shown in Figures 3 and 4, the base 4 has an armrest storage section 7 for storing the armrest 6, located adjacent to the outer side (lower side Z2) of the skin edge 8a. The fixing member 9 is formed of a long, strip-shaped member extending in a second direction D2 that is perpendicular to a first direction D1 (see Figure 6) in which the skin attachment section 12 and the locking section 13 are aligned. Near the center of the strip-shaped member constituting the fixing member 9 in the second direction D2 (the width direction Y of the seat 1 in this embodiment), the locking section 13 is removed to form a slit 22 (see Figures 6 and 7). Therefore, when a user of the seat 1 inserts their finger(s) FR (see FIG. 12 ) into the gap between the armrest 6 and the cover edge 8a to remove the armrest 6 from the armrest storage section 7 of the base body, the cover edge 8a bends toward the inside (upper side Z1) of the base body 4 at the slit 22 of the fixing member 9, making it easier to insert the finger(s) FR into the gap, improving the ease of inserting the finger(s). This makes it easier to remove the armrest 6 from the armrest storage section 7.

[0053] (8) In the seat 1 of this embodiment, the fixing member 9 includes a connecting arm 14 that connects the upholstery attachment portion 12 and the locking portion 13. The connecting arm 14 has a stepped portion 21 that bends in a direction away from the upholstery end portion 8a. Therefore, as shown in FIG. 12 , when a user of the seat 1 inserts their finger FR into the gap between the armrest 6 and the upholstery end portion 8a to remove the armrest 6 from the armrest storage portion 7 of the base body 4, the upholstery end portion 8a bends toward the inside (upper side Z1) of the base body 4 at the stepped portion 21 of the fixing member 9, making it easier to insert the finger FR into the gap, improving the ease of insertion of the finger. This makes it easier to remove the armrest 6 from the armrest storage portion 7.

[0054] (9) In the seat 1 of this embodiment, as shown in FIG. 5, the inner locking piece 18 has an inclined surface 18a that slopes away from the inner surface 4b12 of the locked portion 4b1 toward the tip of the inner locking piece 18.

[0055] According to this configuration, when the locking portion 13 of the fixing member 9 is locked to the locked portion 4b1, the locked portion 4b1 is guided by the inclined surface 18a of the inner locking piece 18, so that the locking portion 13 can easily be locked by sandwiching the locked portion 4b1 between the inner locking piece 18 and the outer locking piece 17. This improves the workability of the operation of locking the fixing member 9 to the locked portion 4b1.

[0056] (10) In the seat 1 of this embodiment, as shown in Fig. 5, the inner protrusion 20 is disposed at the base of the inner locking piece 18. With this configuration, when the skin attachment portion 12 receives tension T from the skin 8 in the direction toward the front surface 4b2 of the upper component 4b, the inner protrusion 20 disposed at the base of the inner locking piece 18 is pressed against the inner surface 4b12 near the tip of the locked portion 4b1, causing the inner protrusion 20 to come into pinpoint contact with the inner surface 4b12 of the locked portion 4b1 (see contact point CP) and bite into the inner surface 4b12, making it less likely to slip and allowing the inner protrusion 20 to function as a fulcrum in a stable manner. As a result, the skin end 8a can be more stably fixed.

[0057] (11) In the seat 1 of this embodiment, as shown in Fig. 5, the lower component 4a of the base 4 has an engaging portion 4a2 that engages with the tip of the cover attachment portion 12 of the fixing member 9. With this configuration, the tip of the cover attachment portion 12 of the fixing member 9 engages with the engaging portion 4a2 of the lower component 4a of the base 4, thereby preventing the cover attachment portion 12 from coming off.

[0058] (12) As described above, the fixing member 9 of this embodiment has a configuration in which the locking portion 13 locked to the locked portion 4b1 is unlikely to come off even when the skin attachment portion 12 receives the tension T of the skin 8 in the direction toward the front surface 4b2 of the upper component 4b. Specifically, the locking portion 13 has an outer locking piece 17 that abuts against the outer surface 4b11 of the locked portion 4b1 and an inner locking piece 18 that abuts against the inner surface 4b12 of the locked portion 4b1, and is locked to the locked portion 4b1 with the outer locking piece 17 and the inner locking piece 18 sandwiching the locked portion 4b1. The inner locking piece 18 has an inner protrusion 20 that protrudes toward the inner surface 4b12 of the locked portion 4b1. The outer locking piece 17 has a protrusion 19 at its tip 17a as a reaction force receiving portion that receives a reaction force F2 from the outer surface 4b11 of the locked portion 4b1.

[0059] 8, in the fixing member 9 of this embodiment, when the skin end portion 8a attached to the skin attachment portion 12 is pulled, the locking portion 13 is locked to the locked portion 4b1 with the outer locking piece 17 and the inner locking piece 18 sandwiching the locked portion 4b1, thereby generating a tension T in the skin end portion 8a in a direction (forward side X1) toward the front surface 4b2 of the upper component 4b of the base 4. This tension T presses (see pressing force F1) the inner protrusion 20 of the inner locking piece 18 against the inner surface 4b12 of the locked portion 4b1 (specifically, the inclined surface 4b13 on the tip side of the inner surface 4b12) at the position of contact point CP, which serves as a fulcrum.

[0060] 9, the protrusion 19 (reaction force receiving portion) at the tip end of the outer locking piece 17 is pressed against the outer surface 4b11 of the locked portion 4b1 and receives a reaction force F2 from the outer surface 4b11, becoming a point of force. The reaction force F2 causes the protrusion 19 to apply an acting force F3 to the skin attachment portion 12 in a direction perpendicular to the direction of the tension T (the vertical direction Z in FIG. 10) and in a direction approaching the locked portion 4b1 (upward direction Z1).

[0061] As a result, as shown in Figure 11, it is possible to balance the rotational moment M1 due to the tension T of the skin 8 that the skin attachment portion 12 receives, with the contact point CP of the inner protrusion 20 as the center of rotation, and the rotational moment M2 due to the acting force F3 that acts on the skin attachment portion 12.

[0062] Therefore, with this fixing member 9, the balance of the two rotational moments M1, M2 acting on the upholstery attachment portion 12 prevents the fixing member 9 from rotating. As a result, the locking portion 13 of the fixing member 9 can maintain a state in which it is locked to the locked portion 4b1 of the base body by sandwiching the locked portion 4b1 from the inside and outside with the outer locking piece 17 and the inner locking piece 18, and the locking portion 13 will not come off the locked portion 4b1. Therefore, no additional member for preventing the locked portion 4b1 from coming off is required in addition to the fixing member 9, and it is possible to stably fix the upholstery edge 8a using only the fixing member 9 without adding any additional parts to the seat 1.

[0063] <Summary of the embodiment> The above embodiment can be summarized as follows. The seat of this embodiment is a seat comprising a base, a skin covering the front surface of the base, and a skin fixing member that fixes an end of the skin to the base at an edge of the rear surface of the base, the base having an engaged portion that protrudes rearward from the edge of the rear surface of the base and has an outer surface facing outward and an inner surface facing inward of the base, the end of the skin extends to the rear surface side of the base beyond the engaged portion, the skin fixing member has a skin attaching portion to which the end of the skin is attached, and a locking portion that is arranged closer to the engaged portion than the skin attaching portion and is locked to the locked portion, the end of the skin is locked to the locked portion via the skin attaching portion, the locking portion has an outer locking piece that abuts on the outer surface of the engaged portion and an inner locking piece that abuts on the inner surface of the engaged portion, the inner locking piece being abutted against the engaged portion of the engaged portion The outer engaging piece has an inner protruding portion that protrudes toward the inner surface, and the outer engaging piece has a reaction force receiving portion at its tip that receives a reaction force from the outer surface of the engaged portion, and the engaging portion is engaged with the engaged portion with the outer engaging piece sandwiched between the outer engaging piece and the inner engaging piece, and the reaction force receiving portion is configured to receive a reaction force from the outer surface of the engaged portion with the inner protruding portion as a fulcrum due to the tension of the skin, and the reaction force receiving portion is configured to receive the reaction force such that the rotational moment caused by the tension of the skin received by the skin attaching portion with the inner protruding portion as the center of rotation and the rotational moment caused by the acting force acting on the skin attaching portion are balanced by the reaction force.

[0064] According to this configuration, the seat includes a skin fixing member that fixes an edge of the skin to the base by being engaged with a locking portion that protrudes rearward from the edge of the rear surface of the base. This skin fixing member is configured so that the locking portion that is engaged with the locking portion is unlikely to come off even when the skin attachment portion receives tension on the skin in a direction toward the front surface of the base. Specifically, the locking portion has an outer locking piece that abuts the outer surface of the locking portion and an inner locking piece that abuts the inner surface of the locking portion. The outer locking piece and the inner locking piece are engaged with the locking portion while sandwiching the locking portion. The inner locking piece has an inner protruding portion that protrudes toward the inner surface of the locking portion. The outer locking piece has a reaction force receiving portion at its tip that receives a reaction force from the outer surface of the locking portion.

[0065] When the locking portion is locked to the locked portion with the outer locking piece and the inner locking piece sandwiching the locked portion, tension is generated at the end of the skin in a direction toward the front surface of the base. This tension presses the inner protrusion against the inner surface of the locked portion, acting as a fulcrum, and the reaction force receiving portion is pressed against the outer surface of the locked portion, receiving a reaction force from the outer surface and acting as a force point. The reaction force applies an acting force to the skin attachment portion in a direction perpendicular to the direction of the tension and in a direction approaching the locked portion, and the reaction force receiving portion receives a reaction force such that the rotational moment caused by the skin tension received by the skin attachment portion about the inner protrusion as the center of rotation balances with the rotational moment caused by the acting force acting on the skin attachment portion, which has become the point of action.

[0066] Therefore, with this skin fixing member, the balance of the two rotational moments acting on the skin mounting portion prevents the skin fixing member from rotating. Therefore, the locking portion of the skin fixing member can maintain its locked state by sandwiching the locked portion of the base body from the inside and outside between the outer locking piece and the inner locking piece, preventing the locking portion from coming off the locked portion. Therefore, no additional retaining member is required for the locked portion, and the edge of the skin can be stably fixed using only the skin fixing member without adding any additional parts to the seat.

[0067] In the above-described seat, it is preferable that the reaction force receiving portion has a protrusion that protrudes from the tip of the outer engaging piece toward the outer surface of the engaged portion.

[0068] With this configuration, the reaction force receiving portion of the outer locking piece has a convex portion that protrudes from the tip of the outer locking piece toward the outer surface of the locked portion, and this convex portion bites into the outer surface of the locked portion, thereby ensuring that the reaction force is received from the outer surface.

[0069] In the above-described seat, it is preferable that the reaction force receiving portion has a tip end portion of the outer engaging piece that is inclined in a direction toward the outer surface of the engaged portion with respect to the extending direction of the skin attachment portion.

[0070] According to this configuration, the reaction force receiving portion of the outer locking piece has a tip portion of the outer locking piece that is inclined in a direction toward the outer surface of the locked portion relative to the direction in which the skin mounting portion extends, so that this inclined tip portion bites into the outer surface of the locked portion, thereby ensuring that the reaction force is received from the outer surface.

[0071] In the above seat, the skin attachment portion preferably has a flat portion that linearly guides the end of the skin toward the rear surface side.

[0072] According to this configuration, the edge of the skin fits along the flat surface of the skin attachment portion, making it possible to maintain a uniform appearance of the seat.

[0073] In the above-mentioned seat, it is preferable that an end portion of the skin is fixed in a state of being looped around the skin attachment portion.

[0074] With this configuration, the edge of the skin is fixed in a state of being looped around the skin attaching part, which makes it possible to firmly fix the edge of the skin to the skin attaching part, and also makes it easier to create a clear and neat seam between the edge of the skin and other components.

[0075] In the above-mentioned seat, the skin attachment portion preferably has a thickness that allows an edge of the skin to be sewn to the skin attachment portion.

[0076] This configuration makes it easier to sew the edge of the skin to the skin attachment part, and also makes it easier to create a clearer and neater seam between the edge of the skin and the other member.

[0077] In the above-described seat, it is preferable that the base has an armrest storage section for storing an armrest at a position adjacent to the outer side of the end of the skin, the skin fixing member is constituted by a long strip-shaped member extending in a second direction perpendicular to a first direction in which the skin mounting section and the locking section are aligned, and a slit is formed in the strip-shaped member near the center in the second direction by removing the locking section.

[0078] According to this configuration, a slit is formed near the center in the direction in which the belt-shaped member constituting the upholstery fixing member extends (the second direction). Therefore, when a seat occupant inserts their finger into the gap between the armrest and the edge of the upholstery to remove the armrest from the armrest storage section of the base, the edge of the upholstery bends inward toward the base at the slit in the upholstery fixing member, making it easier to insert the finger into the gap, improving the ease of inserting the finger. This makes it easier to remove the armrest from the armrest storage section.

[0079] In the above-described seat, it is preferable that the base body has an armrest storage section for storing an armrest at a position adjacent to the outer side of the edge of the skin, the skin fixing member further has a connecting arm section connecting between the skin mounting section and the locking section, and the connecting arm section has a stepped section that bends in a direction away from the edge of the skin.

[0080] According to this configuration, the connecting arm portion of the upholstery fixing member, which connects the upholstery attachment portion and the locking portion, has a stepped portion that is bent in a direction away from the edge of the upholstery. Therefore, when a seat occupant inserts their finger into the gap between the armrest and the edge of the upholstery to remove the armrest from the armrest storage portion of the base, the edge of the upholstery bends inward toward the base at the stepped portion of the upholstery fixing member, making it easier to insert the finger into the gap, improving the ease of inserting the finger. This makes it easier to remove the armrest from the armrest storage portion.

[0081] In the above-described seat, the inner locking piece preferably has an inclined surface that slopes away from the inner surface of the locked portion toward the tip of the inner locking piece. With this configuration, when the locking portion of the upholstery fixing member is locked to the locked portion, the locked portion is guided by the inclined surface of the inner locking piece, making it easier for the locking portion to sandwich the locked portion between the inner and outer locking pieces and lock it. This improves the workability of the operation of locking the upholstery fixing member to the locked portion.

[0082] In the above seat, the inner protrusion is preferably disposed at the base of the inner locking piece.

[0083] With this configuration, when the skin attachment section receives tension from the skin in the direction toward the front surface of the base, the inner protrusion located at the base of the inner locking piece is pressed against the inner surface of the locked section near the tip, causing the inner protrusion to come into pinpoint contact with the inner surface of the locked section and bite into the inner surface, making it less likely to slip and allowing the inner protrusion to function as a stable fulcrum. As a result, the edge of the skin can be more stably fixed.

[0084] In the above seat, it is preferable that the base body further has an engaging portion with which a tip end of the skin attaching portion of the skin fixing member engages.

[0085] According to this configuration, the tip of the skin attaching portion of the skin fixing member engages with the engaging portion of the base body, thereby making it possible to prevent the skin attaching portion from coming off.

[0086] The skin fixing member of this embodiment is a skin fixing member that fixes a skin covering the front surface of a base body of a seat to an engaged portion that protrudes rearward from the edge of the rear surface of the base body, and the skin fixing member includes a skin attaching portion having a shape that allows an end portion of the skin to be attached, and an engaging portion that is engaged with the engaged portion of the base body, the engaging portions have outer and inner engaging pieces that are spaced apart from each other and are able to sandwich the engaged portion from the inside and outside of the base body, the inner engaging piece has an inner protruding portion that protrudes inward into a gap between the outer and inner engaging pieces, and the outer engaging piece has a reaction force receiving portion at its tip that is able to receive a reaction force from the engaged portion, and the skin fixing member is configured such that the engaging portion is fixed to the engaged portion by the outer and inner engaging pieces. When the skin is engaged with the engaged part with the inner protrusion sandwiched between the inner protrusion and the engaged part, tension of the skin is generated at the end of the skin in a direction toward the front surface of the base, and this tension causes the inner protrusion to be pressed against the inner surface of the engaged part, becoming a fulcrum, and the reaction force receiving part is pressed against the outer surface of the engaged part, receiving a reaction force from the outer surface, becoming a force point, and the reaction force receiving part is configured to receive the reaction force such that the reaction force applies an acting force to the skin attachment part in a direction perpendicular to the direction of the tension and in a direction approaching the engaged part, and the reaction force receiving part receives the reaction force such that a rotational moment caused by the tension of the skin received by the skin attachment part with the inner protrusion as the center of rotation is balanced with a rotational moment caused by the acting force acting on the skin attachment part.

[0087] According to this configuration, the skin fixing member that fixes the edge of the skin to the base body of the seat has a configuration in which the locking portion that is locked to the locked portion of the base body is unlikely to come off even when the skin attachment portion receives tension from the skin in a direction toward the front surface of the base body. Specifically, the locking portion has an outer locking piece and an inner locking piece that are spaced apart to form a gap that can sandwich the locked portion. The inner locking piece has an inner protruding portion that protrudes inward from the gap. The outer locking piece has a reaction force receiving portion at its tip that can receive a reaction force from the outer surface of the locked portion.

[0088] In this skin fixing member, the locking portion is locked to the locked portion with the outer locking piece and the inner locking piece sandwiching the locked portion, thereby generating tension in the skin at the end of the skin in a direction toward the front surface of the base, and this tension presses the inner protrusion against the inner surface of the locked portion to become a fulcrum, and the reaction force receiving portion is pressed against the outer surface of the locked portion to receive a reaction force from the outer surface to become a force point. The reaction force applies an acting force to the skin mounting portion in a direction perpendicular to the direction of the tension and in a direction approaching the locked portion, and the reaction force receiving portion receives a reaction force such that the rotational moment due to the skin tension received by the skin mounting portion about the inner protrusion as the center of rotation is balanced with the rotational moment due to the acting force acting on the skin mounting portion.

[0089] Therefore, with this skin fixing member, the balance of the two rotational moments acting on the skin mounting portion prevents the skin fixing portion from rotating. As a result, the locking portion of the skin fixing member can remain locked to the locked portion of the base body by sandwiching it from the inside and outside between the outer locking piece and the inner locking piece, preventing the locking portion from coming off the locked portion. Therefore, it is possible to stably fix the edge of the skin using only the skin fixing member without adding any additional parts to the seat.

[0090] As described above, according to the seat and the upholstery fixing member of this embodiment, the edge of the upholstery can be stably fixed only by the fixing member without adding any additional parts to the seat.

Claims

1. A seat comprising a base, a skin covering the front surface of the base, and a skin fixing member that fixes an end of the skin to the base at the edge of the rear surface of the base, wherein the base has an engaged portion that protrudes rearward from the edge of the rear surface of the base, the engaged portion having an outer surface facing the outside of the base and an inner surface facing the inside of the base, the end of the skin extends toward the rear surface of the base beyond the engaged portion, the skin fixing member has: a skin attachment portion to which the end of the skin is attached, and a locking portion that is positioned closer to the engaged portion than the skin attachment portion and is locked to the engaged portion, the end of the skin is locked to the locked portion via the skin attachment portion, the locking portion has an outer locking piece that abuts against the outer surface of the engaged portion and an inner locking piece that abuts against the inner surface of the engaged portion, the inner locking piece has an inner protruding portion that protrudes toward the inner surface of the engaged portion, the outer locking piece has at its tip a reaction force receiving portion that receives a reaction force from the outer surface of the locked portion, the locking portion being locked to the locked portion with the outer locking piece and the inner locking piece sandwiching the locked portion, and the reaction force receiving portion is configured to receive a reaction force from the outer surface of the locked portion with the inner protrusion as a fulcrum due to the tension of the skin, and the reaction force receiving portion is configured to receive the reaction force such that the rotational moment caused by the tension of the skin received by the skin attachment portion around the inner protrusion as a center of rotation is balanced with the rotational moment caused by the action force acting on the skin attachment portion by applying an acting force to the skin attachment portion in a direction perpendicular to the direction of the tension and in a direction approaching the locked portion due to the reaction force.

2. A seat as described in claim 1, characterized in that the reaction force receiving portion has a protrusion that protrudes from the tip of the outer engaging piece toward the outer surface of the engaged portion.

3. A seat as claimed in claim 1 or 2, characterized in that the reaction force receiving portion has a tip end of the outer locking piece that is inclined in a direction toward the outer surface of the locked portion relative to the extension direction of the skin attachment portion.

4. A seat according to claim 1 or 2, characterized in that the skin attachment portion has a flat portion that linearly guides the edge of the skin toward the rear surface side.

5. A seat according to claim 1 or 2, characterized in that the edge of the skin is fixed in a state of being looped around the skin attachment portion.

6. A seat according to claim 5, characterized in that the thickness of the skin attachment portion is such that the edge of the skin can be sewn to the skin attachment portion.

7. A seat as claimed in claim 1 or 2, wherein the base has an armrest storage section for storing an armrest at a position adjacent to the outside of the edge of the skin, the skin fixing member is constituted by a long strip-shaped member extending in a second direction perpendicular to a first direction in which the skin mounting section and the locking section are aligned, and a slit is formed in the strip-shaped member near the centre in the second direction by removing the locking section.

8. A seat as claimed in claim 1 or 2, wherein the base has an armrest storage section for storing an armrest at a position adjacent to the outer side of the edge of the skin, the skin fixing member further comprises a connecting arm section connecting between the skin mounting section and the locking section, and the connecting arm section has a stepped section that bends in a direction away from the edge of the skin.

9. A seat as claimed in claim 1 or 2, characterized in that the inner locking piece has an inclined surface that slopes in a direction away from the inner surface of the locked portion as it approaches the tip of the inner locking piece.

10. A seat according to claim 1 or 2, characterized in that the inner protrusion is disposed at the base of the inner locking piece.

11. A seat according to claim 1 or 2, characterized in that the base body further has an engaging portion with which the tip of the skin attachment portion of the skin fixing member engages.

12. A skin fixing member for fixing a skin covering the front surface of a base body of a seat to an engaging portion protruding rearward from the edge of the rear surface of the base body, the skin fixing member comprising: a skin attachment portion having a shape to which an end portion of the skin can be attached; and an engaging portion that engages with the engaging portion of the base body, the engaging portion having an outer engaging piece and an inner engaging piece that are spaced apart from each other and can sandwich the engaging portion from the inside and outside of the base body, the inner engaging piece having an inner protruding portion that protrudes inward into the gap between the outer engaging piece and the inner engaging piece, the outer engaging piece having a reaction force receiving portion at its tip that can receive a reaction force from the engaging portion, the skin fixing member is configured such that, when the locking portion is locked to the locked portion with the outer locking piece and the inner locking piece sandwiching the locked portion, tension of the skin is generated at the end of the skin in a direction toward the front surface of the base, and this tension causes the inner protruding portion to be pressed against the inner surface of the locked portion to become a fulcrum, and the reaction force receiving portion is pressed against the outer surface of the locked portion to receive a reaction force from the outer surface to become a force point; and the reaction force receiving portion is configured such that, by the reaction force, it applies an acting force to the skin mounting portion in a direction perpendicular to the direction of the tension and in a direction approaching the locked portion, so that it receives the reaction force such that a rotational moment caused by the tension of the skin received by the skin mounting portion about the inner protruding portion as a center of rotation is balanced with a rotational moment caused by the acting force acting on the skin mounting portion.

Images